I’ve been washing my iPhone a few times a day. Not kidding, once in a few hand washes, usually when I get back home or into the office, I soap up my hands, and then apply some of that watered down soap to the iPhone, staying half an inch away from the speaker hole. I then wash it off with a gentle stream of water (again, making sure that no water goes directly into the speaker holes but if it runs over it I’m not worried).
Given the water tightness rating of the recent iphones and the various submersion tests I’ve seen, I’m not that worried about a little bit of water, and I haven’t had an issue in the 6 months I’ve been doing this.
Of course this should come with the usual disclaimers that Apple doesn’t warranty against water damage and the phone’s water tightness could be impacted by things like drops etc. Do this at your own risk.